1.   But Boston has also taken a utilitarian approach, often going where opportunity knocks in the search for partners.

2.   Amid the tax strategies, opportunity knocks.

3.   And then opportunity knocked.

4.   Bill Hill looks on in amazement, realizing he is watching opportunity knock.

5.   Aikman simply did not deliver when opportunity knocked.

6.   But a woman has the right to change her mind, especially if opportunity knocks.

7.   But for both Mr. President and Mr. Would-be President, opportunity is knocking very loudly.

8.   But the defense is badly hobbled, and what are we to make of an offense that stubbornly refused to open the door when opportunity knocked?

9.   Feldman said his new status would not change the company, other than to give it a greater ability to move quickly when opportunity knocks.

10.   For the Aggies and their ambitions, opportunity has knocked oh-so-seldom.