帮忙翻译几个英语句子

1 You are never too experienced to learn new techniques.
2 There remains one problem, namely, who should be sent to head the research there.
3 Their relationship did meet with some difficulty at the beginning because of cultural differences.
4 Though he has had ups and downs, I believed all along that he would succeed someday.
5 I have some reservations about the truth of your claim.
6 She isn't particularly tall, but her slim figure gives an illusion of height.

1 you again how experienced, also have learning new technology (have) time...
2 there is a problem, that is sent to lead the research. (Use) an appositional benefit
Because of the different culture and 3) at the beginning of their relationship, met with some difficulties really useful. (?)
4. Although he has ups and downs, but I always believe that he will succeed sooner or later. (ups and downs; all a)
5. I told you the truth that have some reservations about (like).
6. She is not particularly high, but her thin, give a person a kind of tall illusion. (I) an illusion