hange the sentences according to directions:

Water is one of the most useful elements in nature. (Positive)

= Very few elements in nature are as useful as water. (one of the very few)

It is a very important asset. (Exclamatory)

= What an important asset it is! (Subject it > what)

We can not pass a single day without water. (Interrogative)

= Can we pass a single day without water? (Negative sentence-এর ক্ষেত্রে not উঠে গিয়ে interrogative)

lts main source is the rain that creates streams, lakes and rivers. (Compound)

= Its main source is the rain and rain creates streams, lakes and rivers.(that দ্বারা rain কে বোঝানোয় 2nd clause-এর subject হিসেবে rain আসবে)

We have rain during the monsoon. (Complex)

= When it is the monsoon, we have rain. (During থাকলে when হয়)

Heavy rainfall often causes flood. (Passive)

= Flood is often caused by heavy rainfall (causes is caused (present indefinite)}

Crops are damaged. (Active)

= Heavy rainfall damage crops. (Subject না থাকায় heavy rainfall আনা হয়েছে)

Our winter is dry and rainless. (Negative)

= Isn't our winter dry and rainless? (অর্থ পরিবর্তন হয়ে যাওয়ার সম্ভাবনা থাকলে negative interrogative করতে হয়)

Docs rainless winter bring good harvest? (Assertive)

= Rainless winter does not bring good harvest. (Interrogative ev positive থাকায় negative assertive হবে।)

We can grow more crops if we can make the best use of rain. (Simple)

= By making the best use of rain, we can grow more crops. (It + positive = by + verb in ing)