The idea is that the matter we see does not have enough gravitational pull to keep galaxies together.
VOA: special.2009.07.21
They had to keep the herd together day and night and protect it from bad men and Indians.
VOA: special.2010.03.18
Material called a growth medium is put on the joint to keep it from getting dry and to help the two plants grow together.
VOA: special.2010.05.18
Anderson knew she would have to work to keep her family together.
VOA: special.2009.01.25
Lincoln fought to keep the Union together.
VOA: special.2009.02.09
Yet as president, Mr.Havel was unable to keep the country together.
VOA: standard.2009.11.17
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