Recently some scientists have concluded that meteorites found on Earth and long believed to have a Martian origin might actually have been blasted free of Mars’s gravity by the impact on Mars of other meteorites.
最近，某些科學家得出結(jié)論認為，那些在地球上發(fā)現(xiàn)的并一直被相信源自火星的隕石(meteorite)，實際上有可能是由于其它的隕石撞擊火星而致使其被震離火星的重力作用范圍。
難句類型：復雜修飾
解釋：這個句子難就難在以that引導的賓語從句，從句中的主語是meteorites，修飾它的成分有兩個，一個是found on Earth，另一個是long believed to have a Martian origin，兩個凍死的成分之間以and 相連接。
注意，這里不能把原句理解成是meteorites found on Earth and meteorites long believed to have a Martian origin的省略形式，這個表達是說有兩種隕石，一種是地球上發(fā)現(xiàn)的，另一種來自于火星，原文所指的是同一批隕石的兩個特征，發(fā)現(xiàn)于地球，來自于火星。
句子最后的by the impact on Mars of other meteorites讀上云令人感到不舒服的原因，是the impact of other meteorites中的impact of 被修飾impact的on Mars分隔開了。
意群訓練：Recently some scientists have concluded that meteorites found on Earth and long believed to have a Martian origin might actually have been blasted free of Mars’s gravity by the impact on Mars of other meteorites.