1.we decided to take rooms in Longwood House Even though we knew we could not afford the rent => In spite of.... 2''Why don't you spent your next summer holiday in Da Nang?''Nhat Anh said to Linh => Nhat Anh suggested....... 3.the number of students studying abroad has increased dramatically in recent years =>there..... 4.He has never taken part in a singing contest => At...... 5.They doesn't have a laptop,so they can't do their English project in the class. => Were......

1. In spite of the fact that we knew we could not afford the rent, we decided to take rooms in Longwood House.

Or: In spite of knowing we could not afford the rent, we decided to take rooms in Longwood House.

   In spite of the fact that + clause, clause

   In spite of + N/V-ing, clause 

2. Nhat Anh suggested Linh (that) she should spend her next summer holiday in Da Nang. 

   S1 + suggest + O + (that) + S2 + should + V +...

3. There has been a dramatic increase of the number of students studying abroad in recent years.

   HTHT: S + has/have + V3/ed + O

   has increased dramatically = has been a dramatic increase

4. At no time has he taken part in a singing contest. 

   At no time = never

   At no time + trợ động từ + S + V

5. Were they to have a laptop, they could do their English project in the class.

   Đảo ngữ câu điều kiện loại 2: Were + S + (not) + to-V...., S + could/would + V