5. I’ve never seen such a strange film before.  

=> This is the first time  I've seen such a strange film

5.1. Ngoc has never eaten such a good meal before.

=> This is the first time Ngoc has eaten such a good meal

5.2. They have never met such a hard test before.

=> This is the first time  they have met such a hard test

5.3. Mr. Phuong has never made such a tasty cake before.

=> This is the first time Mr. Phuong has made such a tasty cake