. -May we leave the classroom now? -No, you ______. You ______ to leave until the bell rings.
–Who is the man ____ blue? –-My English teacher . He is strict _____ the students.
It is _________ difficult work that we can't finish it in a short time.
I still remember the village ________ I grew up.
Do you know if _______ back next week ? If he ________ back , please let me know .
The young trees should______ as often as possible.