08課 絶対〜ない・必ず〜とは言えない 教科書 p.38
Definitely not / not really
接続：普通形 + とは限らない
not necessarily. Reject the assumption that a statement is always true.
注意 / Note：Check the subject, tense and tone of both clauses; Avoid translating word for word from Vietnamese.
比較 / Compare：Compare with similar samples in the same article to choose according to nuance and connection. Same 課: 〜はずがない／〜わけがない／〜わけではない／〜など／〜なんか／〜ことは〜が — these models are often mistaken for each other, read the 接続 line carefully and then decide.
高い物がいいとは限りません。
Expensive things are not necessarily good.
日本人が皆すしを好きだとは限りません。
Not all Japanese people like sushi.
性能が高い機械が、必ずしも使いやすいとは限りません。
A machine with high performance is not necessarily easy to use.