1. Because Tam ate a lot last night, she had a stomachache. 

-> Because of eating a lot last night, she had a stomachache. 

_Because of + N/Ving = Because + MĐ : mặc dù

2. She had tried on all the dresses in the shop before she bought the most expensive one.    
 -> After trying/had tried  on all the dresses in the shop , she bought the most expensive one.    

_After + Ving

_After +QKHT , QKĐ

`#Cam`

`1`.Because of eating a lot last night , Tam had a stomachache

`\rightarrow` Because of + V-ing / N + Clause : Bởi vì

`2`.After she had tried on all the dresses in the shop , she bought the most expensive one

`\rightarrow` After + S + had + V3 / PII , S + Ved / V2

`\text{@ TheFox}`