$\text{8.}$ was shoveling - brought
$\text{→}$ When/ While + QKD/ QKTD, QKD/ QKTD: hành động đang xảy ra thì có 1 hành động khác chen vào
$\text{9.}$ had - was driving - hit
$\text{→}$ "Yesterday" chia thì QKD
$\text{10.}$ decided - were starving
$\text{→}$ "10 years ago" chia thì QKD
$\text{→}$ "At that time" là thời gian xác định ở QK dùng QKTD
$\text{11.}$ were waiting - arrived
$\text{12.}$ was swimming - saw
$\text{13.}$ Were they playing - started
$\text{14.}$ were driving - stopped
$\text{15.}$ was blowing - went