... work is very nice. A. who B. for whom C. whose D. whichCâu 3: He is the boy ______ I went to school. A. with which B. with whom C. to whom D. to whichCâu 4: The house _______ I live is very ... alternative C. alternate D. renewablyĐọc kỹ đoạn văn sau và chọn phơng án đúng( A hoặc B,C,D) cho mỗi câu từ 21đến 25.photovoltaic cellsAs population increases and countries industrialize, ... available, limitless and free, if the equipment is available.The photovoltaic cell is simple. It has a transparent metallic film at the top. Below this is a layer of silicon which is one of the commonest...