—Please ______ us in the discussion.

—I'd like to，but I'm ______busy at the moment.

A．attend；too

B．join；much too

C．take part in；much too

D．join；too much

母乳喂养婴儿，开始添加蛋黄、鱼泥的时间是（）

A.1～2个月

B.2～3个月

C.4～6个月

D.7～9个月

E.半岁后