Bài tập ngữ pháp tiếng anh

... Cum Dong Tif Tieng Anh Bai tap Trac Nghiem Gi6i Tu1Tieng Anh Bai tap Tif Vung Tieng Anh 10 Cac Bai Luan Tieng Anh 11 Bai tap Nguf Phap Tieng Anh 12 Bai tap Thanh NgU Tieng Anh 13 Bai tap Luyen... Nghiem Tieng Anh trinh A B (tap I) Bai tap Trac Nghiem Tieng Anh trinh C (tap II) Bai tap Doc Hieu Tieng Anh Bai tap Dien Tti Tieng AnJi Bai tap Dat Cau Tieng Anh Bai tap Bien Doi Cau Tieng Anh Bai... were you doing at this time yesterday? - Hanh dong dang xay (d qua khOO thi co mot hanh dong khac xen vao (hanh dong dang xay dung Past Continuous, hanh dong xen vao dung Simple Past) Ex: + When