In HSK 3 grammar, under 词类 → 副词 → 时间副词, the forms include: 才1、马上、先、一会儿、刚、刚刚、一直.
才1
马上
mǎshàng
immediately
先
xiān
first
一会儿
yíhuìr
a little while
刚
gāng
just now
刚刚
gānggāng
just; just now
一直
yìzhí
always; straight
暂无。