Matched context for expulsion and back-flow

The page lists matched contexts for expulsion and back-flow.

Share - expulsion	Share - back-flow	Phrase
13.56%	27.51%	prevent {expulsion or back-flow} [perform operation]
16.16%	6.55%	fuel {expulsion or back-flow}
10.38%	9.86%	fluid {expulsion or back-flow}
9.03%	6.12%	gas {expulsion or back-flow}
3.43%	4.08%	air {expulsion or back-flow}