1-started

2-goes

3-find

4-will

1Hoa find play monopoly boring because it difficult

2My brother not like ice-skating because he think it dangerous

II.

$\text{1.}$ started

$\text{→}$ start a hobby = take up a hobby: bắt đầu 1 sở thích

$\text{2.}$ go 

$\text{→}$ go swimming: đi bơi

$\text{3.}$ find

$\text{→}$ find + N/ V-ing + adj

$\text{4.}$ will

$\text{→}$ in the future chia TLD

III.

$\text{1.}$ Hoa finds playing Monopoly boring because it is difficult.

$\text{→}$ find + N/ V-ing + adj

$\text{2.}$ My brother doesn't like ice-skating because he thinks it is dangerous.

$\text{→}$ think + N/ V-ing + is + adj