homework December 14th

Hello!^^

Thank you for sending your homework.

Cheers!
Jean 

1. on call
Firemen are always on call in case of fire.

>> correct

 2. around the clock
The sound of that clock made me awake around the clock.
>> The sound of that clock kept me awake around the clock. [This sentence means that you were awake for 24 hours, not only at night. We don\'t normally use \'around the clock\' in this context.]

 3. calling
I am working as a pastor, and it is my calling which is given from God.
>> I am working as a pastor, and it is my calling that is given by God.

4. head of the family
I am the head of the family that I love and have to support.
>> correct

5. cannot change overnight
My English speaking skill cannot change overnight.
>> correct

>> or: My English speaking competence cannot improve overnight.

6. cannot teach an old dog new tricks
As say that cannot teach an old dog new trick, it cannot easily be changed old habits.

>> As the saying goes, you cannot teach an old dog new tricks because it\'s difficult to change old habits.