Use of the backquote before hours

The backquote must be used before the indication of a time or appointment:

• I can't find you at 8pm.
• How about starting the party at 9 pm?
• I will leave the house at midnight.
• Your appointment is at one in the afternoon.
• João's game is now at 6pm.
• My favorite series is at 10 pm.

When not to use an undertone before hours

We do not use a back-tone before the hour count:

• Did you manage to take the two-hour break recommended by the doctor?
• The three hours of training were very demanding.
• I'll call in an hour to see how you are.
• In the kitchen, the four hours flew by.

We do not use crasis before hours when the hours are accompanied by the prepositions "after, from, between, to".

• Call after at 3:30 pm.
• I've been waiting for him since at nine in the morning.
• The doctor can only attend in between at 9am and 10am.
• The appointment was made for at 1pm.

The crase signals the combination of two letters a: a preposition "a" with an article "a". In this case, as this combination doesn't happen, we don't use the backtape. In the examples above, the "as" that comes before each time (3:30 pm, 9:00 am, 9:00 am, 1:00 pm) is an article.

When the use of the backquote before hours is optional

We may or may not use the backquote if the preposition that is before the hours is the preposition "until":

• The class runs until 10pm. OR The class runs until 10pm.
• I'll be home until 9:00. OR I will be home until 9:00.
• She stayed at her friend's house until ten at night. OR Stayed at her friend's house until ten at night.

Tip to know when to use backquote before hours

You can confirm whether or not to use backquote by replacing anytime with "to the noon". If with this change the phrase makes sense, we use backquote; if it doesn't make sense, we don't use the backtack.

Examples:

• The game starts at 6:30 am. --> The game starts to the noon.
• How about we start the meeting at ten? --> How about we start the meeting to the noon?
• We identified the killer after 8 pm. --> We identified the killer after noon.

Read too:

• Crasis: all about the crasis! When to use and tips
• Super easy tips for knowing when to use CRASE
• Optional Crasis
• Crasis: rules of use

Back exercises before hours

1. (Mackenzie) Tick the alternative that exactly fills in the blanks.

I have been here since ______ 8:00 am, but I can only stay until ______ 9:30 am, because ______ 10:30 am I will attend ______ solemn opening session of an important exhibition of modern art, needing, for this, go to ______ Rua 7 de Abril and go to ______ Galeria “Sanson Flexor".

a) at - at - at - at -a -a
b) at - at - at - at - at - at
c) at - at - at - at - at - at
d) at - at - at - at - at - at
e) at - as - as - at - at - at

See Answer

Alternative d: as - as - to - to - to - to.

• "I've been here since at 8h" - do not use a backquote if before the hours there is the preposition "since".
• "but I can only stay until at or at 9:30 am" - the back is optional after the preposition "until".
• "why at 10:30 am" - an accent is used in the time indication.
• "I will watch à solemn opening session of an important exhibition of modern art" - the verb "assistir" is ruled by a preposition when it indicates presence ("assistirei" has the sense of "presenciarei").
• "needing, for this, to address me à Rua 7 de Abril" - a crasis is used when the verbs indicate destiny (to drive me).
• "and go à Gallery “Sanson Flexor”" - a crasis is used when the verbs indicate destiny (to go).

2. Indicate the only wrong prayer and correct it.

a) I danced the 6 hours of the party.
b) The party started at 6 pm.
c) Dinner will be served after 8pm.
d) The party runs until 6 am.

See Answer

Alternative c. Correction: Dinner will be served after 8pm.
Do not use crasis if before the hours there is the preposition "after".

As for the remaining alternatives:

a) I danced the 6 hours of the party.
It does not use an accent in the indication of counted hours, only in the clock time.

b) The party started at 6 pm.
It uses an accent in the time indication.

d) The party runs until 6 am.
The use of the crase is optional after the preposition "until", so it is also correct: The party goes on until 6 am.

3. Indicate the right and wrong alternatives.

a) I can stay until eleven at night.
b) Two hours of lunch passed in an instant.
c) I go to work at both.
d) The start of the congress is scheduled for 10am.
e) I can go after 7pm.
f) She must arrive between 6pm and 7pm.
g) There will be no transportation from 9am to 10am.
h) I have been waiting standing since seven in the morning.

See Answer

Are correct: a), d), e), g).

a) I can stay until eleven at night.
After the preposition "until" the use of the back is optional. So, they are correct:
I can stay until eleven pm. and I can stay until eleven pm.

d) The start of the congress is scheduled for 10am.
Do not use a crase if before the hours there is the preposition "to".
e) I can go after 7pm.
Do not use crasis if before the hours there is the preposition "after".

g) There will be no transportation from 9am to 10am.
In the time indication, we always use a double back. Exceptions are only for cases where the prepositions "after, from, between, to" precedes the hours.

Correction of the rest:

b) The two hours of lunch passed in an instant.
An accent is not used in the indication of counted hours, only in the time indication of the watch.
c) I go to work at two.
The backquote is always used in the clock's hour indication.
f) She should arrive between 6pm and 7pm.
Do not use a crasis if before the hours there is the preposition "between".
h) I have been waiting standing since seven in the morning.
Do not use a crasis if before the hours there is the preposition "since".

Keep training your knowledge: Crasis Exercises