Without all the facts, Helen could only conjecture a solution.
由于事实还没有全部完备,海伦只能臆测解决的方法。
I'm afraid I can't agree with you. That's a good way of giving information, but it's not a good way of persuading people. For one thing, it's boring, and people aren't going to read an ad that looks boring. For another thing, one computer looks very like