CR section in SAT

<p>First of all, i came to America about a year ago, so my English is not that good. When i take the critical reading section, i always got like 500 to 600, but the thing is they are really inconsistent…; i got 600 on one day and got 480 on another day…
The problem is that i often don’t understand the sentence even if i know all words in the sentence. Thus, i normally understand the passage and pick the main point of the each paragraph, but i often fail to get the details of passages, which causes me to get the detail questions wrong. In this case, what should i do? Should i keep taking practice SAT? I want people whose second language is English to answer my question… and one more question is that do people whose first language is English often not understand the sentence even if they know all the words in the sentences? I’m just curious… Thank you ^^ </p>