I read more books _____ I can catch up with my classmates.
I saw him when I passed by.
Bob used to ________in the countryside . But now he is used to _________in the big city .
---You’d better not eat too much salt. It's bad for your health. ---- _______________.
Yesterday, they talked about something important _______ the phone.
His father told him ________ his best friend to dinner this Sunday.