پرسش‌ها با تگ (گرامر انگلیسی)

Manufacturing is Canada’s most important economic activity, ………….. 17 percent of the workforce.

 ………….. is rooted in experiments in iron and steel conducted in the nineteenth century.

During the course of its growth, a frog undergoes a true metamorphosis ……… with  a fishlike larval stage.  

……… their differences, the three models resemble ……… in a crucial respect. 

-……… their differences, the three models resemble ……… in a crucial respect. 

کجا If و کجا Whether به کار ببریم؟

کجا tell و کجا say به کار ببریم؟

تفاوت معنایی و کاربرد هر کدوم چیه؟ در چه شرایطی از apply for   و  در چه شرایطی از apply to  استفاده میشه؟

I think not یا I don't think so? یا هر دو؟

Medical research at the cellular level, ……… research on the immune system, has been  made possible through twentieth-century advances in techniques of genetic research.