1.i'm sure you were proud of your son's success(must) -->you............ 2.she/want/meet/people/come/other/countries 3.the bags/make/leather/be/sell/out/sales/last year

1. You must be proud of your son's success.

S + must + V + O .... proud of là adj

2. She wants to meet people from other countries.

S + want to + V0 + O 

3. The bags made of leather are sold out of sales last year.

We use made of when we talk about the basic material or qualities of something.

We often use made from when we talk about how something is manufactured

1. You must be proud of your son's success.

2. She wants to meet people from other countries.

3. The bags made of leather are sold out of sales last year.