As far as vocabulary teaching is concerned, which of the following is NOT the uncertainty that still remains?

(单选题)Ben Velzian’s experience indicates that ______. (单选题)In which column of a newspaper may the article appear? (单选题)What’s the problem of the semiconductor approach? (单选题)Which of the following statements about YInMn is NOT mention (单选题)She kept her head down, not ______ to attract attention. (单选题)It’s a pity you failed this time. ______, it’s also a good t (单选题)The man ______ are very sad when they think of their relativ (单选题)______ you’ve known him very well, you should support him to (单选题)When you have sent the message, don’t forget to call the man (单选题)His daughter, who is ______, is said to be a genius on calcu