DETROIT — Perhaps it’s a sign of maturation that the Lions weren’t hooting and hollering after their 40-9 shellacking of the New England Patriots on Thursday night. 

Perhaps they know they have much work to do.

And, after all it is the preseason.

Here are five things we learned:

1. They missed Calvin Johnson again. His presence changes the way defenses play. It also gives them opportunities that no one else does. Jim Schwartz said it was a last-minute decision. Better to get him to 100 percent for the regular season because they will need him.

2. Reggie Bush is a slippery guy. Just when you think he’s done he picks up a few more yards. He had five catches for 103 yards including a 67-yarder that he wanted to take all the way in. It’s like he’s the No. 2 receiver but he isn’t. Another dimension to the offense.

3. If the defensive line can dominate like it did in the first half, this should be fun to watch. In the first quarter the defense forced four turnovers — that’s against Tom Brady and the Patriots. Not a bad night’s work. They also pressured Brady who didn’t throw for a touchdown, although he did pass for 185 yards.

4. The secondary has to tighten up a bit. Brady threw four passes for 19 yards o more. Although on a 20-yard completion Glover Quin forced a fumble and Louis Delmas recovered it. Rookie Darius Slay started giving us a look at the potential starting secondary for the regular season opener — Slay, Chris Houston (who intercepted Brady), Delmas and Quin.

5. The personal fouls have to be reduced or eliminated. Nick Fairley was whistled on the second snap for illegal use of hands. He was playing hard so you can almost forgive that but seven snaps later he gets called for unsportsmanlike conduct. A few series later C.J. Mosley is penalized for a personal foul. So when Willie Young taunted Tom Brady after an incompletion (what was he thinking?), Schwartz had all he could take. That was Young’s last snap.

(Follow @PaulaPasche on Twitter. Order her book,  “100 Things Lions Fans Should Know & Do Before They Die’’ here. It’s also available at bookstores.)