Amy and Frank went to the concert, but ______ of them enjoyed the performance.

Thanks a lot for the trouble you ______ tohelp us

下列各句中，没有语病的一项是（ ）

erstand the grammar of thesentence, you must break it ____into parts.

Warmblooded animals live an active life even in freezing winter, which helps them to________their normal body temperature. [ ]