In order to improve your writing, you’d better write          .

 –Why has Tom looked unhappy recently? –He has some difficulty ______ with his new classmates at school.

 Dogs are kept to ______ the houses from thieves at night.

— Hi, what’s the rush?— I am off to the library right now to            a seat for my roommate!

The captain told the sailors to their sprits when they were on the point of giving up.