Use gerund or infinitive. Remember the difference in the meaning of the verb with gerund and infinitive.
1. Helen needs (to know) French frequently if she wants to work there.
2. The doctor advised (to use) more vegetables in the diet.
3. John regretted (to write) these rude letters to her.
4. Nick often forgets (to call) his granny
5. He’ll remember (to meet) them in Paris last Monday.