Task: Question Answering
Input (English): Passage: Following their first win of the season, the Colts faced another divisional rival in the Tennessee Titans. After being forced to punt on their first offensive drive, the Colts' defense forced a fumble that was recovered by Ricky Jean-Francois and set up the Colts inside Titan territory. After a 37-yard pass from quarterback Andrew Luck to T. Y. Hilton set the Colts up at the one yard line, Trent Richardson scored on the next play, putting the Colts up 7-0. An onside kick gave the ball back to the Colts, which led to an eleven play, 44-yard drive that ended in a touchdown pass from Luck to Dwayne Allen. The Colts' defense again forced a turnover on the Titans' next possession, with Charlie Whitehurst throwing an interception to Mike Adams. Luck and the Colts' offense again drove down the field, though this time having to settle for a field goal, extending the lead to 17-0. Tennessee scored their first points midway through the second quarter on a Ryan Succop. The Colts responded on their next possession with a 30-yard field goal from Adam Vinatieri. A Luck interception late in the half, set up the Titans in Colts' territory and allowed them to score on a pass from Whitehurst to Delanie Walker, cutting the Colts' lead to 20-10 at halftime. The Colts' scored on their first offensive possession of the second half, on a 28-yard touchdown pass from Luck to Reggie Wayne and then later in the quarter on a pass from Luck to Coby Fleener, extending the Colts' lead to 34-10. Tennessee responded with an eight play, 80-yard drive that ended with a touchdown run from Bishop Sankey. Luck completed his fourth touchdown pass of the game early in the fourth quarter, this time on a 15-yard pass to Ahmad Bradshaw, giving the Colts a 41-17 lead. Late in the game, Adams again forced another turnover, with Zach Mettenberger throwing the interception. During the game, Reggie Wayne caught seven passes for 119 yards and one touchdown, which was enough to move him to seventh on the NFL all-time receptions list and tenth on the most receiving yards list. With the win, the Colts improved to 2-2. 
Question: How many touchdowns did Luck throw for? 
Answer type: Number 
Output (English): 4.