Question:
Who was the chair of Comintern in Apr, 1926?

Context:
 Grigory Zinoviev is the chair of Comintern from Mar, 1919 to Jan, 1926. 
 Georgi Dimitrov is the chair of Comintern from Jan, 1929 to Jan, 1943. 
 Nikolai Bukharin is the chair of Comintern from Jan, 1926 to Jan, 1929.

Answer:
Question:
Who was the chair of Comintern in Apr, 1926?

Context:
 Grigory Zinoviev is the chair of Comintern from Mar, 1919 to Jan, 1926. 
 Georgi Dimitrov is the chair of Comintern from Jan, 1929 to Jan, 1943. 
 Nikolai Bukharin is the chair of Comintern from Jan, 1926 to Jan, 1929.

Answer:
user
Nikolai Bukharin
assistant
Question:
Who was the chair of Comintern in Apr, 1926?

Context:
 Grigory Zinoviev is the chair of Comintern from Mar, 1919 to Jan, 1926. 
 Georgi Dimitrov is the chair of Comintern from Jan, 1929 to Jan, 1943. 
 Nikolai Bukharin is the chair of Comintern from Jan, 1926 to Jan, 1929.

Answer:
user
Grigory Zinoviev
Georgi Dimitrov
assistant
Question:
Who was the chair of Comintern in Apr, 1926?

Context:
 Grigory Zinoviev is the chair of Comintern from Mar, 1919 to Jan, 1926. 
 Georgi Dimitrov is the chair of Comintern from Jan, 1929 to Jan, 1943. 
 Nikolai Bukharin is the chair of Comintern from Jan, 1926 to Jan, 1929.

Answer:
user
Nikolai Bukharin
assistant