پرسش‌ها با تگ (گرامر انگلیسی)

The versatility of modern cross-country skiing equipment allows skiers ………  technique to diverse terrain.  

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؟

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