1 deficient

2 to owe

3 to lack

4 yawn

1 yawn

1 in arrears

2 behind in payments

3 to default on one's debts

1 suboptimal

2 subpar

3 not good enough

1 to owe a debt

2 the sum owed

1 all we need is an east wind (idiom); lacking only one tiny crucial item

1 lit. everything is ready, all we need is an east wind (idiom)

2 fig. lacking only one tiny crucial item

1 everything is ready, all we need is an east wind (idiom)

2 lacking only one tiny crucial item

3 also written 萬事俱備，只欠東風|万事俱备，只欠东风