请问 we study hard study是及物动词吗 请问bird can fl

We study English very hard So We must Study hard we students should study hard为什么hard要在study. study是动词不定式吗?能单独做谓语吗?we study hard这句话有没有问题? 请问：It's time for us___(study) hard. 请问一个语法问题；English is hard to study,to study 在句中作什么状语啊 study hard all we need is to study hard 这句话是病句吗?如果是,怎么改? she doesn't study hard ,其中hard是副词吗? He said to us that we should study hard.这个句子是正确的吗? how can we study english?—we can study by . We must study English hard or we can't be in the library,(反义