這英文句子是否正確

意見如下：

我個人認為應該在 "the top range" 之前加一個介詞 (preposition)，用來表示「我知道在他正就讀的小學裏，其學業成績是在 "最高水平的組別"之內 」的意思。

另外， "current"有無亦可。如想強調「他」曾就讀另一間小學，有 "previous school" 的存在，就應使用 "current"。

值得注意的是，因為句中的 "know" 用了past tense，是否想表達「知道」已經是過去的事? 如果是這樣，講者所知道的事也是過去的資訊，宜用past tense或past perfect tense。

因此，句子可修訂如下：
I knew that his academic performance had been within the top range in his primary school.


有關 "range" 用法的參考資料：
http://hk.dictionary.yahoo.com/search.html?q=1&s=range&Submit=+%ACd%A6r+

no
I knew that his academic performance has been the top range in his current primary school.

has been 之後應該加個過去分詞 例如reached to

yes.I knew that his academic performance has been the top range in his current primary school.

解釋:我知道他的學業成績是在他的當今的國小的最高的範圍。