a packet of candies \\
a pail of water \\
a shaft of light \\
a hail of criticism \\
a swarm of bees \\
a loaf of bread \\
a troop of soldiers \\
a mass of people \\
a bunch of flowers \\
old gang of friends \\
a flock of sheep (小动物群）\\
a herd of sheep （大动物群牲口群）\\