frank
adj
(-er, -est) ~ (with sb) (about sth) showing thoughts and feelings openly; honest and direct in speech; plain and blunt 公开表达思想感情的; 言语真诚的; 坦率的; 坦白的; 直率的
a frank reply, discussion, exchange of views, etc 坦率的回答、 讨论、 交换意见等
To be (perfectly) frank with you, I think your son has little chance of passing the exam. 说实在的, 我认为你儿子这次考试及格的希望不大.
frank v [Tn]
put a mark or a stamp on (a letter, etc) to show that postage has been paid or does not need to be paid 在(信件等)上做记号、 加印记(以示邮资己付或免费邮寄).
I suggest that we ask users of this machine what they think about it. We can photograph them using it too. Then we can put their comments at the top of the advertisement in big print. We can bring in some humour too. People enjoy reading humorous ads.