解释下列词语

①龙城飞将         ②不教

把下面的红苹果按字母发音的口型大小排序。

用括号里所给动词的适当形式填空。
(1)He often ____ (study) with his friends in the library after class.
(2)We should do more exercise ____  (keep) healthy.
(3)These magazines must not ____  (take) out of the reading room.
(4)  I called you this morning, but nobody answered it.
     Oh, we ____ (run) in the park.
(5)Jacky Chen ____  (star) in many action films for many years. I admire him very much.

用亲本基因型为DD和dd的植株进行杂交，对其子一代的幼苗用秋水仙素处理产生了多倍体，其基因型是（　　）