This research regards language teaching as a whole system, including mother tongue teaching and English teaching. Each system includes listening, speaking, reading and writing.

视整个语言教学为一个系统，包括母语教学和英语教学两个分系统，每种语言教学系统又都包括听、说、读、写四个部分。

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The FAA gave Boeing permission last month to test the revamped system, which includes additional insulation around each of the battery's eight cells to prevent a short circuit or fire in one of the cells from spreading to the others.

NPR: FAA Approves Resumption Of Boeing 787 Flights