"I can speak English and French fluently” Nam said to Ba.

⇒ Nam said to Ba/told Ba (that) he could speak English and French fluently.

→ câu gián tiếp dạng trần thuật: S + said/told + O/ said to + O (that) + S + V(lùi thì)

* Một số thì của động từ lùi thì:

- HTĐ → QKĐ

- HTTD → QKTD

- HTHT → QKHT

- HTHTTD → QKHTTD

- QKĐ → QKHT 

- QKTD → QKHTTD

- is/am/are going to → was/were going to

- can/ will/ shall/ may/ must + V0 → could/ would/ should/ might/ had to + V0

I can speak English and French fluently " Nam said to Ba "

⇒ Nam said to Ba that he could speak English and French fluently .

Công thức " S + said / told + O / said to + O ( that ) + S + V ( lùi lại thì ) "