—Did your father come back early last night?
—Yes. It was not yet eight o’clock _______ he arrived home.
| A．before | B．when | C．that | D．until |
Not knowing how to grow crops，the primitive people had no ______ but to gather the fruit and hunt animals for food.
| A．conception | B．command | C．virtue | D．alternative |
—Did you meet with the famous star yesterday?
—______ I had come a little earlier!
| A．If only | B．Only if | C．But for | D．For fear |
A lot of children never fully ______ their mothers until it is too late.
| A．urge | B．appreciate | C．accuse | D．motivate |
______ I admit that there are problems, I don't agree that they cannot be solved.
| A．As | B．If | C．While | D．When |
_______I had time, I would have visited the beautiful lake again.
| A．If | B．Unless | C．Had | D．When |