From Twitter
I'm not sure _____ to class even if the Corona Virus State of Emergency ends. I prefer online study; it's smarter, safer, easier and saves me money & time. (Both choices are grammatically correct, but one is useless and means something very different from the other.)
Choices:
to go
about going
In my opinion there are two reasons to offer here.
日本語訳
「たとえ新型コロナウイルスによる緊急事態宣言が解除されても、授業へ行くかどうか迷っています。オンライン学習のほうが賢明で安全、簡単で、時間とお金も節約できるので好きです。」空欄には to go と about going のどちらが入るでしょうか。どちらも文法上は可能ですが、意味が異なります。
解答・解説
The answer is about going, because:① when we are or are not sure regarding something, we use 'about' as the preposition to connect the subject to the object we are discussing.
Examples:
I'm sure about this information. Trust me.
I'm not sure about this. We'd better check it on Wikipedia.
John is sure about the spelling; he looked it up in the dictionary.
Similarly, we use sure about with the 'ing' form of verbs as nouns (called gerunds).
Examples:
I'm sure about depending on this information. Trust me.
I'm not sure about trusting this information; we'd better check it on Wikipedia.
John is not sure about spelling this word; he couldn't find a dictionary to use.
And the answer is "about going" because ② 'not sure to' means "not certain" from the point of view of others, just as "sure to" means "certain" from the point of view of other people, not from the point of view of the speaker. Look:
It's sure to rain.
Nature is not sure about rain coming--or happening. The situation is certain, or we are certain... that rain will come.
Bob is sure to be here on time. He is never late.
We are sure about it; Bob is not thinking about it.
We use about (meaning "regarding" or "concerning", whereas sure to means "supposed to" or "expected to."
After I'm not sure, we need a noun in this sentence, and about is the right preposition to precede a noun. We use about with true nouns and proper nouns all the time. Look:
I like books about traveling in space. Or... I like books to travel in space.
'Traveling in space' is not a verb, and it doesn't look like a verb, either, but if we replace it with t0 travel in space, it looks like a verb and sounds like a verb and the whole meaning of the sentence changes to "I like books as a method of traveling in space." It's like the speaker flies on books and not in spaceships!
So, About is used to mean regarding, "concerning" and "in the case of" and that is what we need after "I'm not sure."
ここで言いたい「授業へ行くことについて迷っている」なら I'm not sure about going to class です。about は「～について」という意味で、名詞や動名詞 going につなぎます。「この情報が正しいか確信がない」「この情報を信じてよいか迷う」なども not sure about ... と言えます。
sure to ... は「きっと～する」のように、出来事が起こる見込みを表すことがあります。Bob is sure to be here on time は「ボブはきっと時間どおりに来る」。これは本人が迷っているかどうかを述べているわけではありません。books about traveling in space は「宇宙旅行についての本」ですが、books to travel in space だと「宇宙旅行をするための本」のように意味が変わります。
原文中の例文には不自然なものがあります。ここでは主な対比を説明し、問題文の英語そのものは変更していません。