tim thai 6 tuần downtime Tim thai sẽ xuất hiện ở tuần thứ 5 hoặc thứ 6 của thai kỳ và có thể nghe thấy nhịp tim thông qua siêu âm thai. Đa phần, bác sĩ sẽ dùng thiết bị siêu âm để giúp mẹ nghe nhịp tim thai nhi vào khoảng tuần thứ 6 hoặc tuần thứ 7
it is a long time since we last met 1 It is a long time since we last met. =We haven't met each other for a long time. 2 When did you have it? =How long have you had it? 3 This is the first time I had such a delicious meal. = I haven't eaten such a delicious meal before. 4 I haven't seen him for 8 days. = The last time I saw him was 8 days ago. 5 I haven't taken a bath
optimize Learn the meaning of optimize, a verb that means to make something as good or effective as possible. See how to use optimize in different contexts, such as business, science, and technology, with examples from the Cambridge English Corpus
