"He can speak French very well." 是对的。 还有“He speaks French very well" 也对，没有"can"的话。 要说"He can (动词)"的话，动词不会用"ｓ"。　 但是你要说“He (动词) very well" 的话，你得用这个"ｓ"。 对不起我的汉语不太好，我想你看懂我的说明。:)

Definitely (1) !! He is 3rd person singular, so if you didn't use "can" then it would be "he speaks French very well". But since you use the can, then the correct answer is "He can speak French very well".