Cách 1:

Số học sinh nữ lớp 4B là:

\(35.\dfrac{2}{5}=14\left(hs\right)\)

Số học sinh nam lớp 4B là:

\(35-14=21\left(hs\right)\)

Cách 2:

Số học sinh nam bằng \(1-\dfrac{2}{5}=\dfrac{3}{5}\) số học sinh cả lớp.

\(\Rightarrow\) Số học sinh nam lớp 4B là:

\(35.\dfrac{3}{5}=21\left(hs\right)\)

10. disapprova \(\Rightarrow\)  disapproval

3. unsucessful \(\Rightarrow\) unccessfull

Some mistake in your answer:

circumtances \(\Rightarrow\) circumstances

attention at the same time \(\Rightarrow\) attention to at the same time

To sumary \(\Rightarrow\) To summary / To summarize

necessary only for people \(\Rightarrow\) necessary for people 

live the time being \(\Rightarrow\) live for the time being

6. dictricts \(\Rightarrow\) districts

Gọi số đó là \(\overline{abcd}\) \(\left(a\ne0\right)\)

Ta có: \(\overline{abcd}+a+b+c+d=2020\)

\(\Leftrightarrow1000a+100b+10c+d+a+b+c+d=2020\)

\(\Leftrightarrow1001a+101b+11c+2d=2020\)

Gọi số đó là \(\overline{abcd}\) \(\left(a\ne0\right)\)

Ta có: \(\overline{abcd}+a+b+c+d=2020\)

\(\Leftrightarrow1000a+100b+10c+d+a+b+c+d=2020\)

\(\Leftrightarrow1001a+101b+11c+2d=2020\)

\(\text{https://www.testbig.com/ielts-writing-task-ii-ielts-general-training-essays/american-film-actor-once-said-tomorrow}\)

_{You should argue and prove your assertions or thoughts.}

these risk in advance \(\Rightarrow\) these risks in advance

taking precautionary measures \(\Rightarrow\) take precautionary measures

come true \(\Rightarrow\) comes true

these government \(\Rightarrow\) these governments

compare \(\Rightarrow\) compared