Manyothernewtechniquesarenowavailablethatenablemoreresearch___(do)inthetesttubetoseeifchemicalsproduceharmfulbiologicaleffects.
劲度系数为k的轻弹簧竖直悬挂，下端连接质量为m的小球，将小球在弹簧原长位置由静止释放，弹簧的最大伸长量为（）
Iwouldverymuch______tovisitsomeoftheplacesthatIhavebeenreadingabout.
Hetookhisumbrellawithhimlestit____(rain).
Canyoutellusmore___(precise)whathappenedlastnight?
